Use UV as a faster pip implementation

[Arusekk]

Closes #2490

[Arusekk]

Okay: for some reason this breaks PLT emulation (so unicorn?), breaks it consistently, and only breaks it on py3.10.

Why? No idea yet.

[Arusekk]

>>> import unicorn
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.venv/lib/python3.10/site-packages/unicorn/__init__.py", line 4, in <module>
    from .unicorn import Uc, ucsubclass, uc_version, uc_arch_supported, version_bind, debug, UcError, __version__
  File "/.venv/lib/python3.10/site-packages/unicorn/unicorn.py", line 14, in <module>
    from .unicorn_py3 import *
  File "/.venv/lib/python3.10/site-packages/unicorn/unicorn_py3/__init__.py", line 1, in <module>
    from .unicorn import *
  File "/.venv/lib/python3.10/site-packages/unicorn/unicorn_py3/unicorn.py", line 236, in <module>
    uclib = __load_uc_lib()
  File "/.venv/lib/python3.10/site-packages/unicorn/unicorn_py3/unicorn.py", line 123, in __load_uc_lib
    import pkg_resources
ModuleNotFoundError: No module named 'pkg_resources'

[Arusekk]

Okay, this is a thing probably on Unicorn's side: unicorn-engine/unicorn#2122

[Arusekk]

Huh?

https://github.com/astral-sh/uv/blob/83f1b8b0f13713f2413ae9b96c64da0cedcf5fb8/crates/uv/src/commands/venv.rs#L354-L365

        // Resolve the seed packages.
        let requirements = if interpreter.python_tuple() >= (3, 12) {
            vec![Requirement::from(
                uv_pep508::Requirement::from_str("pip").unwrap(),
            )]
        } else {
            // Include `setuptools` and `wheel` on Python <3.12.
            vec![
                Requirement::from(uv_pep508::Requirement::from_str("pip").unwrap()),
                Requirement::from(uv_pep508::Requirement::from_str("setuptools").unwrap()),
                Requirement::from(uv_pep508::Requirement::from_str("wheel").unwrap()),
            ]
        };

It seems venv does seed itself, but not venv-less things.

[Arusekk]

Blocked: waiting for Unicorn 2.1.4.

[cclauss]

Please fix git conflicts.

[Arusekk]

Note setup-uv@v6 brought a usability impairment (astral-sh/setup-uv#381).

[Arusekk]

Nope, still blocked, waiting for unicorn 2.1.5 (2.1.4 has broken MIPS).

[cclauss]

ModuleNotFoundError: No module named 'pkg_resources'

Some of the pkg_resources code is still available in modern setuptools.
% uvx --with=unicorn python3.14 -c 'import unicorn'
% uvx --with=setuptools,unicorn python3.14 -c 'import unicorn'